Contrary to closed incubators, thermotherapy devices that are completely open above the reclining surface for premature and newborn patients offer a substantially better access for care and therapy measures at the patient. Open thermotherapy devices are also called open patient care units. However, temperature stabilization and air conditioning suitable for the patient continues to be a technical challenge in such thermotherapy devices. According to DE 103 20 195 B4 or DE 10 2004 016 080 A1, the microclimate above the reclining surface of an open thermotherapy device is embodied by air flows from discharge channels along the sides of the reclining surface. To minimize the energy consumption, the air flows are returned or recycled especially through an exhaust unit arranged fittingly on the head side above the reclining surface.
Regardless of whether single-layer or two-layer air flows are used on the particular sides of the reclining surface, the discharges are directed at a constant angle to the reclining surface and/or at a constant angle to the head-side exhaust unit. Moreover, the velocity distributions of the air flows along the respective discharge channels remain constant. Due to the constant angles and constant velocities over the course of the sides of the reclining surface, shears develop between the individual air flows, which lead to swirling and consequently to an extensive instability of the microclimate. In addition, the constant velocity in terms of direction and value leads to a predetermined discharge directed towards the exhaust unit.
On the other hand, incubators completely closed by limiting walls offer the great advantage of a stable and readily controllable climate in the interior space, so that the premature or newborn patients enjoy an especially adequate, physiologically desired accommodation and air conditioning.